We all forget from time to time. We forget things like people's names or where we put that darn pencil! However, there are more severe cases of memory loss. Memory loss, generally called amnesia, can result from brain damage. People with amnesia can no longer acquire or retain long-term declarative memory. This memory loss can occur in the form of anterograde amnesia, where the patient is unable to recall events occurring after the onset of brain damage, but is able to remember earlier events. Another form of memory loss is retrograde amnesia, is the opposite of anterograde amnesia. However, patients often suffer from both anterograde and retrograde amnesia, thus making them unable to recall memories or form new ones.
In many mild cases, such as those caused by concussion, the person can't recall the blow to the head or their recovery time, but the rest of their memory is intact. Infantile amnesia, or the inability to remember anything at all from the first few months or years of life, is universal. This is suspected to be due to the fact that the memory processes of the brain take time to develop.
